<?php
/*
 *  $Id: NestedSet.php 7490 2010-03-29 19:53:27Z jwage $
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * This software consists of voluntary contributions made by many individuals
 * and is licensed under the LGPL. For more information, see
 * <http://www.doctrine-project.org>.
 */

/**
 * Doctrine_Tree_NestedSet
 *
 * @package     Doctrine
 * @subpackage  Tree
 * @license     http://www.opensource.org/licenses/lgpl-license.php LGPL
 * @link        www.doctrine-project.org
 * @since       1.0
 * @version     $Revision: 7490 $
 * @author      Joe Simms <joe.simms@websites4.com>
 * @author      Roman Borschel <roman@code-factory.org>
 */
class Doctrine_Tree_NestedSet extends Doctrine_Tree implements Doctrine_Tree_Interface
{
	private $_baseQuery;
	private $_baseAlias = "base";

	/**
	 * constructor, creates tree with reference to table and sets default root options
	 *
	 * @param object $table                     instance of Doctrine_Table
	 * @param array $options                    options
	 */
	public function __construct(Doctrine_Table $table, $options)
	{
		// set default many root attributes
		$options['hasManyRoots'] = isset($options['hasManyRoots']) ? $options['hasManyRoots'] : false;
		if ($options['hasManyRoots']) {
			$options['rootColumnName'] = isset($options['rootColumnName']) ? $options['rootColumnName'] : 'root_id';
		}

		parent::__construct($table, $options);
	}

	/**
	 * used to define table attributes required for the NestetSet implementation
	 * adds lft and rgt columns for corresponding left and right values
	 *
	 */
	public function setTableDefinition()
	{
		if (($root = $this->getAttribute('rootColumnName')) && (!$this->table->hasColumn($root))) {
			$this->table->setColumn($root, 'integer');
		}

		$this->table->setColumn('lft', 'integer', 4);
		$this->table->setColumn('rgt', 'integer', 4);
		if ($level = $this->getAttribute('levelColumnName')) {
			$this->table->setColumn($level . ' AS level', 'integer', 2);
		} else {
			$this->table->setColumn('level', 'integer', 2);
		}
	}

	/**
	 * Creates root node from given record or from a new record.
	 *
	 * Note: When using a tree with multiple root nodes (hasManyRoots), you MUST pass in a
	 * record to use as the root. This can either be a new/transient record that already has
	 * the root id column set to some numeric value OR a persistent record. In the latter case
	 * the records id will be assigned to the root id. You must use numeric columns for the id
	 * and root id columns.
	 *
	 * @param object $record        instance of Doctrine_Record
	 */
	public function createRoot(Doctrine_Record $record = null)
	{
		if ($this->getAttribute('hasManyRoots')) {
			if ( ! $record || ( ! $record->exists() && ! $record->getNode()->getRootValue())
			|| $record->getTable()->isIdentifierComposite()) {
				throw new Doctrine_Tree_Exception("Node must have a root id set or must "
				. " be persistent and have a single-valued numeric primary key in order to"
				. " be created as a root node. Automatic assignment of a root id on"
				. " transient/new records is no longer supported.");
			}

			if ($record->exists() && ! $record->getNode()->getRootValue()) {
				// Default: root_id = id
				$identifier = $record->getTable()->getIdentifier();
				$record->getNode()->setRootValue($record->get($identifier));
			}
		}

		if ( ! $record) {
			$record = $this->table->create();
		}

		$record->set('lft', '1');
		$record->set('rgt', '2');
		$record->set('level', 0);

		$record->save();

		return $record;
	}

	/**
	 * Fetches a/the root node.
	 *
	 * @param integer $rootId
	 * @todo Better $rootid = null and exception if $rootId == null && hasManyRoots?
	 *       Fetching with id = 1 is too magical and cant work reliably anyway.
	 */
	public function fetchRoot($rootId = 1)
	{
		$q = $this->getBaseQuery();
		$q = $q->addWhere($this->_baseAlias . '.lft = ?', 1);

		// if tree has many roots, then specify root id
		$q = $this->returnQueryWithRootId($q, $rootId);
		$data = $q->execute();

		if (count($data) <= 0) {
			return false;
		}

		if ($data instanceof Doctrine_Collection) {
			$root = $data->getFirst();
			$root['level'] = 0;
		} else if (is_array($data)) {
			$root = array_shift($data);
			$root['level'] = 0;
		} else {
			throw new Doctrine_Tree_Exception("Unexpected data structure returned.");
		}

		return $root;
	}

	/**
	 * Fetches a tree.
	 *
	 * @param array $options  Options
	 * @param integer $fetchmode  One of the Doctrine_Core::HYDRATE_* constants.
	 * @return mixed          The tree or FALSE if the tree could not be found.
	 */
	public function fetchTree($options = array(), $hydrationMode = null)
	{
		// fetch tree
		$q = $this->getBaseQuery();

		$depth = isset($options['depth']) ? $options['depth'] : null;

		$q->addWhere($this->_baseAlias . ".lft >= ?", 1);

		// if tree has many roots, then specify root id
		$rootId = isset($options['root_id']) ? $options['root_id'] : '1';
		if (is_array($rootId)) {
			$q->addOrderBy($this->_baseAlias . "." . $this->getAttribute('rootColumnName') .
                    ", " . $this->_baseAlias . ".lft ASC");
		} else {
			$q->addOrderBy($this->_baseAlias . ".lft ASC");
		}

		if ( ! is_null($depth)) {
			$q->addWhere($this->_baseAlias . ".level BETWEEN ? AND ?", array(0, $depth));
		}

		$q = $this->returnQueryWithRootId($q, $rootId);

		$tree = $q->execute(array(), $hydrationMode);

		if (count($tree) <= 0) {
			return false;
		}

		return $tree;
	}

	/**
	 * Fetches a branch of a tree.
	 *
	 * @param mixed $pk              primary key as used by table::find() to locate node to traverse tree from
	 * @param array $options         Options.
	 * @param integer $fetchmode  One of the Doctrine_Core::HYDRATE_* constants.
	 * @return mixed                 The branch or FALSE if the branch could not be found.
	 * @todo Only fetch the lft and rgt values of the initial record. more is not needed.
	 */
	public function fetchBranch($pk, $options = array(), $hydrationMode = null)
	{
		$record = $this->table->find($pk);
		if ( ! ($record instanceof Doctrine_Record) || !$record->exists()) {
			// TODO: if record doesn't exist, throw exception or similar?
			return false;
		}

		$depth = isset($options['depth']) ? $options['depth'] : null;

		$q = $this->getBaseQuery();
		$params = array($record->get('lft'), $record->get('rgt'));
		$q->addWhere($this->_baseAlias . ".lft >= ? AND " . $this->_baseAlias . ".rgt <= ?", $params)
		->addOrderBy($this->_baseAlias . ".lft asc");

		if ( ! is_null($depth)) {
			$q->addWhere($this->_baseAlias . ".level BETWEEN ? AND ?", array($record->get('level'), $record->get('level')+$depth));
		}

		$q = $this->returnQueryWithRootId($q, $record->getNode()->getRootValue());

		return $q->execute(array(), $hydrationMode);
	}

	/**
	 * Fetches all root nodes. If the tree has only one root this is the same as
	 * fetchRoot().
	 *
	 * @return mixed  The root nodes.
	 */
	public function fetchRoots()
	{
		$q = $this->getBaseQuery();
		$q = $q->addWhere($this->_baseAlias . '.lft = ?', 1);
		return $q->execute();
	}

	/**
	 * returns parsed query with root id where clause added if applicable
	 *
	 * @param object    $query    Doctrine_Query
	 * @param integer   $root_id  id of destination root
	 * @return Doctrine_Query
	 */
	public function returnQueryWithRootId($query, $rootId = 1)
	{
		if ($root = $this->getAttribute('rootColumnName')) {
			if (is_array($rootId)) {
				$query->addWhere($root . ' IN (' . implode(',', array_fill(0, count($rootId), '?')) . ')',
				$rootId);
			} else {
				$query->addWhere($root . ' = ?', $rootId);
			}
		}

		return $query;
	}

	/**
	 * Enter description here...
	 *
	 * @param array $options
	 * @return unknown
	 */
	public function getBaseQuery()
	{
		if ( ! isset($this->_baseQuery)) {
			$this->_baseQuery = $this->_createBaseQuery();
		}
		return $this->_baseQuery->copy();
	}

	/**
	 * Enter description here...
	 *
	 */
	public function getBaseAlias()
	{
		return $this->_baseAlias;
	}

	/**
	 * Enter description here...
	 *
	 */
	private function _createBaseQuery()
	{
		$this->_baseAlias = "base";
		$q = Doctrine_Core::getTable($this->getBaseComponent())
		->createQuery($this->_baseAlias)
		->select($this->_baseAlias . '.*');
		return $q;
	}

	/**
	 * Enter description here...
	 *
	 * @param Doctrine_Query $query
	 */
	public function setBaseQuery(Doctrine_Query $query)
	{
		$this->_baseAlias = $query->getRootAlias();
		$query->addSelect($this->_baseAlias . ".lft, " . $this->_baseAlias . ".rgt, ". $this->_baseAlias . ".level");
		if ($this->getAttribute('rootColumnName')) {
			$query->addSelect($this->_baseAlias . "." . $this->getAttribute('rootColumnName'));
		}
		$this->_baseQuery = $query;
	}

	/**
	 * Enter description here...
	 *
	 */
	public function resetBaseQuery()
	{
		$this->_baseQuery = $this->_createBaseQuery();
	}
}
